STATCOM modeling impact on wind turbines' Low Voltage Ride Through capability

Ideal Static Compensator (STATCOM) modeling may be deceiving for determining the protection device settings that will operate to fulfill Low Voltage Ride Through (LVRT) requirements of wind turbines. If these settings are not accurately calculated, premature tripping or machines instability may occur and hence LVRT will not be achieved in such cases. Therefore, a more realistic STATCOM model is introduced in this paper and compared to the ideal one. Squirrel Cage Induction Generator (SCIG) based wind turbines are studied using a simplified approach based on torque speed characteristics of induction machines. The transient stability margin is proposed as an indicator for LVRT capability. Theoretical expectations are verified by digital simulation using EMTDC simulation package.